The Open UniversitySkip to content
 

A search for H2 emission in bipolar nebulae and regions of interstellar shock

Phillips, J. P.; White, G. J. and Harten, R. (1985). A search for H2 emission in bipolar nebulae and regions of interstellar shock. Astronomy & Astrophysics, 145(1) pp. 118–126.

Full text available as:
[img]
Preview
PDF (Version of Record) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (236Kb)
URL: http://adsabs.harvard.edu/full/1985A&A...145..118P
Google Scholar: Look up in Google Scholar

Abstract

We report a H2 emission survey of five bipolar outflow sources (NGC 1333, M2-9, As 353, S106, V645 Cyg), and one region of shock interaction between an H II region and molecular cloud (NGC 281). Two of the sources (M2-9, NGC 1333) were detected in the v = 1-0S(1), and Q-branch transitions of H2, and we provide a detailed analysis and modelling for these cases. The probable mass of shocked H2 is shown to range between 1.4 10-6 and 4.2 10-8 M for M2-9, and ≈ 2.5-4 and 1.9-10 M in the case of NGC 1333, although the latter values may require increasing by a factor of a few when due allowance is made for extinction. A detailed analysis for the core of M2-9 indicates that the ionized zone is extremely compact, and our Brackett line measures support other evidence in suggesting a high core extinction, large emission measure E~4 1010 cm-6 pc, and a projected angular radius θc~0.04. Similarly, it is apparent from the H2S(1) line strength that the core expansion velocity must be low and less than ~ 1 km s-1 (a constraint which is also required on dynamical grounds). Finally, CO J = 3-2 observations of the source failed to detect emission above a 2σ limit of T*R ~ 0.4 K, and this is shown to imply a probable expansion timescale of ≲2 103 yr.

Item Type: Journal Article
Copyright Holders: 1985 European Southern Observatory
ISSN: 1432-0746
Keywords: infrared astronomy; nebulae; shock wave interaction; stellar spectra; Balmer series; gas-gas interactions; HII regions; infrared spectroscopy; near infrared radiation
Academic Unit/Department: Science > Physical Sciences
Interdisciplinary Research Centre: Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR)
Item ID: 33778
Depositing User: Glenn White
Date Deposited: 07 Jun 2012 15:28
Last Modified: 26 Oct 2014 08:42
URI: http://oro.open.ac.uk/id/eprint/33778
Share this page:

Actions (login may be required)

View Item
Report issue / request change

Policies | Disclaimer

© The Open University   + 44 (0)870 333 4340   general-enquiries@open.ac.uk